The sum of the number of first and second nearest neighbors in an $FCC$ closed packing is:

Which of the following is correct for the crystal lattices mentioned below?

Which one possesses an antifluorite structure?

An element has a body-centered cubic $(BCC)$ structure with an edge length of $288 \ pm$. The density of the element is $7.2 \ g/cm^3$. How many atoms are present in $208 \ g$ of the element?

Coordination number of $Zn^{2+}$ in $ZnS$ (zinc blende) is

In a crystal of substance $A_xB_y$,$A$ atoms are present at each corner of the face-centered cubic $(FCC)$ unit cell,and $B$ atoms are present at each face center. What is the correct formula of the substance $A_xB_y$?